药渣与煤共热解动力学模型及逸出气红外特性分析

利用TG-FTIR对红霉素药渣、烟煤及共热解过程及热解产物进行分析,研究了添加药渣对烟煤热解过程的影响。在40种固相反应机制函数中,采用Freeman-Carroll积分法推断药渣、烟煤单独热解及共热解过程的最佳反应机理函数,结果显示,药渣单独热解及共热解过程符合Avrami-Erofeev方程(n=4)模型,而烟煤的3个热解阶段分别符合反Jander方程、Avrami-Erofeev方程(n=4)、Jander方程三维扩散(n=2)模型;对共热解lnA与E分析,表明共热解过程存在动力学补偿效应。对共热解逸出气的红外分析表明:药渣单独热解及共热解过程除CO2、CO气体逸出外,还有部分醛类、酮类、羧酸类、酯类等小分子物质逸出,而烟煤单独热解气体主要成分为CO2、CO和CH4;药渣的添加使可燃气体逸出增多,有利于热解气溢出到燃烧后期燃烧室的预混燃烧,扩散混合条件大大改善。

Dynamic model and their gas evolution analysis of co-pyrolysis of bituminous coal and residue blends

Co-pyrolysis of bituminous coal,mixed with erythromycin residue with low ash content and high calorific value was carried out using a thermogravimetric analyzer(TGA) coupled with a Fourier transform infrared(FTIR) spectrometer in N2 atmosphere.Pyrolysis characteristic and pollutant emission performance from bituminous coal and erythromycin residue blends at different mass proportions were studied.Freeman-Carroll integral method was used to infer the best reaction mechanism function for the co-pyrolysis process from 40 kinds of mechanism function of solid-state reaction.Results showed that residue pyrolysis alone and co-pyrolysis process accord with Avrami-Erofeev equation(n=4) model,but the bituminous coal's three stages of pyrolysis respectively in accordance with the Jander equation,the Avrami-Erofeev equation(n=4),Jander equation of three-dimensional diffusion(n=2) model.The co-pyrolysis presented kinetic compensation effect exsists from the linear relationship between lnA and E.FTIR analysis indicated that main gas products of pyrolysis were some aldehydes,ketones,carboxylic acids,esters and other small molecules escape in addition to CO2,CO in residue pyrolysis alone and co-pyrolysis process.The pyrolysis process of bituminous coal alone released mainly ingredients including CO2,CO and CH4.Increasing residue could add combustible gas escape,promote the premixed combustion of post-combustion,improve diffusion mixed conditions greatly.